One of the earlier race inspired scooters by Suzuki, featuring upside-down Showa forks and Carbon fibre look dash panels, the Suzuki Katana was an instant hit and quickly became popular for tuning, with plenty of performance race parts from Malossi and numerous other manufacturers.
Early Suzuki Katana’s had the Suzuki air cooled engine in them, whilst later Suzuki Katana’s had Suzuki’s new liquid cooled engine, and where designated AY50R for katana store the race production version.
One notable feature of the Suzuki Katana’s are their very low gearing, which means the engine does more revolutions per wheel revolution compared to other scooters, this provides very quick acceleration but a lower top speed, even on tuned engines, most other derestricted scooters can keep up on top speed, but will struggle to match a race tuned Suzuki Katana on shear acceleration.
Although some people see the Suzuki Katana’s low gearing as a problem, it is also the scooters greatest strength, with blisteringly fast acceleration, most other scooters will struggle to keep up with it in an urban environment, as even when others are tuned and kitted up with performance parts they’ll still struggle to match the Suzuki Katana’s 0-30 times. When the liquid cooled Suzuki Katana is tuned it is practically untouchable against all the other 50cc scooters on the market in these times, it’ll only loose out on longer roads where speeds of 50mph+ can be achieved by other LC scooters.
The Suzuki Katana’s are primarily restricted mostly in the exhaust, so in the very early models it requires binning and replacing with a race exhaust, whilst in the later versions with a 2 part exhaust, you can grind out the internal restrictor cone and refit the exhaust, although nothing will match the performance that an aftermarket race exhaust gives for the Suzuki Katana. On the very early models, the CDI is also restricted and requires replacing with an aftermarket model, although this isn’t a problem on the later scooters.
As with my usual reccommendation, Gianelli Exhausts generally make the best performance exhausts for scooters, and since they’re all e-marked, completely road legal and come with a warrenty when fitted by an authorised mechanic, so are by far the best tuning option for road going Suzuki Katana’s, and all other scooters that are being tuned for the road.
When fitting a Gianelli race exhaust to your Katana, it’ll require a slightly higher jet (0 to 2 sizes on non catalysed Suzuki Katana’s, I don’t think they made any with catalytic converters) and slightly lighter rollers, since performance exhausts allow the Katana to make more power but at a higher rpm. Going 0.5 – 1 gram lighter than standard generally does the trick for Gianelli race exhausts on the Katana’s, but it varies between exhausts and tunes, and the Suzuki takes 17×12mm rollers.
After fitting a race exhaust, the biggest benefit the Scooter Katana will gain is by fitting a performance big bore kit, adding a 40% increase in capacity and more than doubling the power. Malossi and Polini make the best big bore kits available for tuning the Suzuki Katana, and will provide the best performance and reliability compared to the cheaper big bore kits on the market . As you’re increasing the capacity with the big bore kit, a bigger jet is required to be fitted in the carb, usually around 6-8 sizes larger, although doing a plug chop after a test ride to check the jetting is recommended to check your scooter isn’t running lean after it’s tuning, otherwise it can be liable to go bang.